Hand-operated chain hoist



June 4, 1963 c. CARROLL 3,092,369

HAND-OPERATED CHAIN HOIST Filed Jan. 6. 1960 5 Sheets-Sheet 1 @ar 6% Chan/c765 June 4, 1963 c. CARROLL HAND-OPERATED CHAIN HOIST 5 Sheets-Sheet 2 Filed Jan. 6. 1960 QZZTOJFOPX,

June 4, 1963 c. CARROLL 3,092,359

HAND-OPERATED CHAIN E-IOIST Filed Jan. 6, 1960 5 Sheets-Sheet 3 Jae/"enter I affix/ deg June 4, 1963 Filed Jan. 6. 1960 c. CARROLL 3,092,369

HAND-OPERATED CHAIN HOIST 5 Sheets-Sheet 4 Ira/grew! %r6@s @rro June 4, 1963 c. CARROLL 3,092,359

HAND-OPERATED CHAIN HOIST Filed Jan. 6. 1960 5 Sheets-Sheet 5 Mm)! Ckarezs Carra? 3,092,369 Patented June 4, 1963 3,092,369 HAND-OPERATED CHAIN HOIST Charles Carroll, Danville, 111., assignor to Dun-Norton Company, Pittsburgh, Pa. Filed Jan. 6, 1960, Ser- No. 848 Claims. (Cl. 254-470) The present invention relates to a hand-operated hoist, and more specifically to a hand-operated hoist of the type generally employed with a chain as the principal lifting element.

In the use of hoists, particularly with manually-operated hoists, it oftentimes becomes desirable to lift a load at right angles with the hand chain. With such an action, the dynamic forces operate in perpendicular planes rather than the conventional parallel planes. This relationship contributes toward dynamic balance. Heretofore, undue weight, size, and mechanical inefiiciencies have prevented the development of a commercially successful hoist of this character. A worm gear type hoist requires two sprockets and two load sheaves in order to adequately balance the load and driving force in a conventional right angle hoist.

In view of the foregoing, it is a general object of the present invention to provide a hand-operated hoist in which the load chains and hand chains lie in perpendicular planes. A related and equally important general object of the invention is to furnish a hand-operated hoist which is substantially lighter in weight than competitive hoists of similar capacities.

Another and still important object of the invention is to furnish a hand-operated hoist which achieves an optimum balance throughout the entire range from static no-load to dynamic full-load conditions.

Still another object of the invention is to provide a hand-operated hoist in which the gear mesh reactive forces are distributed more evenly throughout the hoist frame penmitting a more efficient and uniform stressing of the hoist frame.

Yet another object of the invention is to provide a hand hoist organization which can accommodate gear ratios of 11:1, 17:1, and 25:1 without significant design alterations between the respective gear ratios.

Another important object of the invention is to achieve all of the foregoing objectives with a construction which actually offers increased safety to the operator.

Further objects and advantages of the present invention will become apparent as the following description of an illustrative embodiment proceeds, taken in conjunction with the accompanying drawings in which:

FIGURE 1 is a perspective view, partially diagrammatic, showing an operator using a hoist with the general external configuration of the illustrative embodiment to be described;

FIG. 2 is a perspective exploded View of the internal drive mechanism of the illustrative hoist;

FIG. 3 is a front elevation of the gear and pinion employed for achieving the right-angle drive;

FIG. 4 is a diagrammatic partially exploded perspective view of a portion of the working members shown in FIG. 2, but as viewed from the left end of the elements in FIG. 2;

FIG. 5 is a front elevation, partially broken, of the illustrative hoist showing the hand chain, hand chain pawl, a portion of the safety brake and the chain stop;

FIG. 6 is a side elevation of the hoist as shown in FIG. 5 illustrating the right-angle relationship between the load chain and the hand chain;

FIG. 7 is an enlarged, transverse, sectional view of the hoist shown in FIG. 6 taken along a plane run through the center of the hand chain and pinion drive shaft but showing the pinion drive shaft and chain in unsectioned form;

FIG. 8 is an enlarged sectioned end view looking toward the gear pinion taken along the lines generally indicated as 8--8 in FIG. 7; and

FIG. 9 is a transverse sectional view looking down on the drive pinion and sprocket along the section line generally indicated as 9-9 in FIG. 7.

While the details of construction of the preferred embodiment will be set out specifically hereinafter, the subject hoist comprises, in broad outline, a screw-type gear assembly having a single screw type pinion and a single screw-type gear. While it is contemplated that various gears such as hypoid gears, modified worm gears, and the like may be employed, the subject hoist finds unusual utility with screw-type gears of the character disclosed in United States Patents Nos. 2,696,125 and 2,731,886. It is with the geometrical relationship of the gear shaft axes, load axes, and suspension axes that the present construction finds critical relationships and similarly achieves its advantageous operation as to lightness, stability, and safety. As the details of construction are described, the planes of the various axes will also be described along with their relative relationships.

Referring now to FIGURE 1, it will be seen that the hoist 10, shown suspended from a monorail 11 by means of a trolley 12 employs a hand chain 14 and load chain 15 in such a manner so that the plane 16 in which the load chain 15 is oriented intersects along an imaginary line 18 with the plane 19' in which the hand chain 14 is oriented. With a hoist achieving this perpendicular relationship of chains, unusual stability during both dynamic and static load conditions can be achieved.

As will become apparent as the detailed description proceeds, this stable relationship is achieved with a single screw-type gear assembly 20 as shown in best detail in FIGS. 2 and 3. A suitable form of such gears is an arrangement of the type disclosed in United States Patents Nos. 2,696,125 and 2,731,886. As described in the aforesaid patents, this is a skew-axis worm gearing arrangernent involving a face-type worm gear 21 and a conical pinion 22 which has been found to have an excellent adaptability to design variations in gear ratios. In addition, the skew-axis worm gearing such as disclosed provides for intimate contact between several gear surfaces throughout all ranges of operation. Such a meshing increases the safety factor inherent in the hoist substantially over known hoists of similar capacities, weights, and gear ratios.

An additional geometric arrangement of the orientation of the hoist elements appears best in FIG. 7. A plane P passes through the support hook 24, runs perpendicular to the axis of the conical pinion 22 and passes through the area in which the conical pinion 22 meshes with the face-type worm gear 21. In FIG. 8, it will be seen that a piarie P passing through the sprocket assembly 25 also passes through the axis of the support hook 24. Referring to FIGURE 9, it will be further seen that a third plane P", passing through the longitudinal axis of the conical pinion 22 and perpendicular to the axis of the sprocket assembly 25, lies at a mid-point between the face-type worm gear 21 and the chain sprocket 26. It is through the geometrical relationship of these principal members that the unusual static-dynamic load balance relationship exists while still employing only a single gear to accomplish the necessary gear reduction to drive the chain sprocket 26.

Additionally, as will be seen by comparing FIGURES 7 and 8, complete roller bearing friction of all moving parts is accomplished by use of four roller bearings. Specifically, in FIGURE 7, it will be seen that the screwtype gear assembly drive shaft 20 is journaled by a pinion ball bearing 28 and a hand chain wheel ball bearing 29. Sliding contact in the drive between the hand chain wheel 30 and the sprocket 26 is limited chiefly to the mesh between the pinion 22 and gear 21. In FIGURE 8, it will be observed that the sprocket 26 is flanked by a worm gear ball bearing 31 and sprocket ball bearing 32.

With the advantage of the screw-type gear assembly 20 of increased safety attributable to the number of teeth in contact, a related problem arises as to lubrication and friction. It has been found that even with a cast gear and its attendant surface irregularities, a cadimum plating of the surface of the gear teeth after casting and cleaning will increase the mechanical efficiency markedly, and such treatment of the screw-type worm gear assembly 20 is recommended for the preferred embodiment. Increases in mechanical efficiencies in excess of may be achieved in this manner.

The safety brake 40 includes a ratchet 41 which is yieldably engaged by a pawl 42 as illustrated in FIG. 5. The ratchet is permitted to rotate freely on the hub 45. The hub 45 is splined at its inner portion for a longitudinal sliding fit along the spline 46 of the conical gear drive assembly 20. A thread 48 is provided on the end of the pinion gear drive shaft 20 to engage a mating thread 49 interior of the hand chain wheel. The hub 45 is provided with a braking collar 50 with an inner face 51 which abuts against a rear brake disc 52. A front brake disc 54 along with the rear brake disc 52 flank the ratchet 41, with the front brake disc 54 abutting a braking face 55 on the hand chain wheel.

The brake assembly elements are so proportioned 5H3 oriented as to positively lock the load against lowering by means of the pawl 22 engaging the ratchet 41, whereas this positive locking can be disengaged frictionally for either raising or lowering the load by means of reversing the direction of rotation of the hand chain wheel 30. A safety pin 56 is additionally provided for engagement with a thread stop ring 58, the thread stop ring 58 being splined at its center bore for attachment at the end of the spline 46 of the pinion drive shaft assembly 20.

To insure additional safety in operation, a chain guide member 59 (see FIG. 8) is provided to lead the chain into the sprocket 26. Additionally, a chain stripper 60 having a sprocket cleaning finger 61 is provided directly beneath the sprocket 26. The stripper 60 serves to additionally guide the chain as well as extend its finger 61 into the pocket of the sprocket 26 in order to clean the sprocket and prevent chain links from being retained therein.

The cover plates, as pointed out earlier, can be readily removed by removing the cover bolts 39. The hook 24 may be removed by removing the hook pin and the hook mounting collar. The sprocket drive shaft assembly 20 is secured in place against the worm gear 21 by means of a worm gear lock nut.

In review, it will be seen that the foregoing arrangement permits gear ratios with an unusual variation within a single basic design; ratios varying from 11:1 for a one-ton capacity hoist to a 17:1 for a two-ton hoist and 25 :1 for a three-ton hoist may all be achieved. The stability between static no load and dynamic full-load conditions is very good, and lightweight aluminum housings can be employed because of the reduction in weight of the gear assembly.

Although particular embodiments of the invention have been shown and described in full here, there is no intention to thereby limit the invention to the details of such embodiments. On the contrary, the intention is to cover all modifications, alternatives, embodiments, usages and equivalence of the hand-operated chain hoist as fall within the spirit and scope of the invention, specification and the appended claims.

I claim:

1. A manually operated hoist comprising, in combination, a housing, a sprocket, a chain wheel, a sprocket drive shaft, a chain wheel drive shaft, the sprocket and chain wheel shafts being at right angles to each other, a screw-type gear assembly having a single screw-type pinion and a single screw-type gear, the screw-type pin ion being attached to the end of the chain wheel drive shaft and the screw-type gear being in mesh with said pinion and attached to the sprocket drive shaft, a hanging hook secured to the upper portion of the housing and mounted therein for rotation about a vertical axis, the chain wheel drive shaft being oriented between the hook and the sprocket drive shaft, the foregoing elements being oriented so that one plane passed through the hook vertical axis and perpendicular to the sprocket drive shaft would bisect the sprocket, and another plane passed through the hook vertical axis and perpendicular to the chain wheel drive shaft would pass through the meshing area between the screw-type pinion and screw-type gear whereby the hoist is balanced throughout the range of static and dynamic loading while the load and drive are applied in perpendicular planes.

2. A manually operated hoist comprising, in combination, a housing, a sprocket, a chain wheel, a sprocket drive shaft, a chain wheel drive shaft, the sprocket and chain wheel drive shafts being at right angles to each other, a separate pair of ball bearings journalling each of the sprocket and chain wheel drive shafts disposed so that each said pair respectively flanks said sprocket and said chain wheel, a screw-type gear assembly having a single screw-type pinion and a single screw-type gear, the screw-type pinion being attached to the end of the chain wheel drive shaft to extend in cantilever fashion past the bearing most remote from the chain wheel and the screwtype gear being attached to the sprocket drive shaft to mesh with said pinion, a hanging hook secured to the upper portion of the housing and mounted therein for rotation about a vertical axis, the chain wheel axis passing between the sprocket drive shaft axis and the hanging hook, the foregoing elements being oriented so that one plane passed through the hook vertical axis and perpendicular to the sprocket drive shaft would bisect the sprocket, and another plane passed through the hook vertical axis and perpendicular to the chain wheel drive shaft would pass through the meshing area between the screw-type pinion and screw-type gear whereby the hoist is balanced throughout the range of static and dynamic loading while the load and drive are applied in perpendicular planes.

3. In a hoist of the character defined in claim 8, a ratchet wheel, a pawl on the frame selectively engageable with the ratchet wheel to lock the ratchet wheel against rotation in one direction, a hub having a threaded end and splined centrol bore, a spline on the chain wheel drive shaft with which the hub is engaged, a threaded central bore on the chain wheel for engagement with the threaded end of the hub, a collar on the hub at the opposite end of the hub, said collar having a braking face perpendicular to the axis of the hub, and a pair of annular brake disks flanking the ratchet wheel for engagament with the ratchet wheel, chain wheel, and hub.

4. A manually operated hoist comprising, in combination, a housing, a sprocket, a chain wheel, a sprocket drive shaft, a chain wheel drive shaft, the sprocket and chain wheel drive shafts being at right angles to each other, first and second separate pairs of ball bearings respectively flanking said sprocket and said chain wheel and respectively journalling each of the sprocket and chain wheel drive shafts, a screw-type gear assembly having a screw-type pinion and screw-type gear, the screwtype pinion being attached to the end of the chain wheel drive shaft to extend in cantilever fashion past the bearing most remote from the chain wheel and the screwtype gear being attached to the sprocket drive shaft to mesh with said pinion, a hanging hook secured to the upper portion of the housing and mounted therein for rotation about a vertical axis, the elements being oriented so that one plane passed through the hook vertical axis and perpendicular to the sprocket drive shaft would bisect the sprocket, and so that a second plane passed through the hook vertical axis and perpendicular to the chain wheel drive shaft would pass through the meshing area between the screw-type pinion and screw-type gear, the axis of the pinion being oriented so that the axis of the sprocket drive shaft is farther remote from the hook than the pinion axis, whereby the hoist is balanced throughout the range of static and dynamic loading while the load and drive are applied in perpendicular planes.

5. A manually operated hoist comprising, in combination, a housing, a sprocket, a chain wheel, a sprocket drive shaft, a chain wheel drive shaft, the sprocket and chain wheel drive shafts being at right angles to each other, a separate pair of ball bearings journalling each of the sprocket and chain wheel drive shafts, a screw-type gear assembly having a screw-type pinion and screw-type gear, the screw-type pinion being attached to the end of the chain wheel drive and the screw-type gear being attached to the sprocket drive shaft, a hanging hook secured to the upper portion of the housing and mounted therein for rotation about a vertical axis, the elements being oriented so that one plane passed through the hook vertical axis and perpendicular to the sprocket drive shaft would bisect the sprocket, and a second plane passed through the hook vertical axis and perpendicular to the chain wheel drive shaft would pass through the meshing area between the screw-type pinion and screw-type gear, and a third vertical plane passed through the long axis of the chain wheel drive shaft would pass between the sprocket and the screw-type gear, and the axis of the sprocket is below the axis of the screw-type pinion, whereby the hoist is balanced throughout the range of static and dynamic loading while the load and drive are applied in perpendicular planes.

References Cited in the file of this patent UNITED STATES PATENTS 802,890 Schmick Oct. 24, 1905 1,756,459 Gormley Apr. 29, 1930 1,949,920 Robertson Mar. 6, 1934 2,085,815 McCollum July 6, 1937 2,393,120 Perrnan Jan. 15, 1946 2,503,682 Parker Apr. 11, 1950 2,756,614 Kobayashi July 31, 1956 FOREIGN PATENTS 1,453 Great Britain Jan. 21, 1909 

1. A MANUALLY OPERATED HOIST COMPRISING, A COMBINATION, A HOUSING, A SPROCKET, A CHAIN WHEEL, A SPROCKET DRIVE SHAFT, A CHAIN WHEEL DRIVE SHAFT, THE SPROCKET AND CHAIN WHEEL SHAFTS BEING AT RIGHT ANGLES TO EACH OTHER, A SCREW-TYPE GEAR ASSEMBLY HAVING A SINGLE SCREW-TYPE PINION AND A SINGLE SCREW-TYPE GEAR, THE SCREW-TYPE PINION BEING ATTACHED TO THE END OF THE CHAIN WHEEL DRIVE SHAFT AND THE SCREW-TYPE GEAR BEING IN MESH WITH SAID PINION AND ATTACHED TO THE SPOCKET DRIVE SHAFT, A HANGCHAIN WHEEL DRIVE BEING ORIENTED BETWEEN THE HOOK AND THE SPROCKET DRIVE SHAFT, THE FOREGOING ELEMENTS BEING ORIENTED SO THAT ONE PLANE PASSED THROUGH THE HOOK VERTICAL AXIS AND PERPENDICULAR TO THE SPROCKET DRIVE SHAFT WOULD BISECT THE SPROCKET, AND ANOTHER PLANE PASSED THROUGH THE HOOK VERTICAL AXIS AND PERPENDICULAR TO THE CHAIN WHEEL DRIVE SHAFT WOULD PASS THROUGH THE MESHING AREA BETWEEN THE SCREW-TYPE PINION AND SCREW-TYPE GEAR WHEREBY THE HOIST IS BALANCED THROUGHOUT THE RANGE OF STATIC AND DYNAMIC LOADING WHILE THE LOAD AND DRIVE ARE APPLIED IN PERPENDICUALR PLANES. 